Little Stephen B, Jones Richard A, Grattan-Smith J Damien
Department of Radiology, Children's Healthcare of Atlanta, 1001 Johnson Ferry Road, Atlanta, GA 30342, USA.
Pediatr Radiol. 2008 Jan;38 Suppl 1:S106-24. doi: 10.1007/s00247-007-0669-9. Epub 2007 Dec 11.
This article builds on the previous article in this symposium and shows how MR urography contributes to the postoperative evaluation of children with UPJ obstruction. By analyzing the postoperative results, we derived new insights into their preoperative evaluation. With MR urography we combine simultaneous physiological and anatomic evaluation that enables us to identify changes in renal pathophysiology that occur in association with impaired drainage and obstruction. We studied 35 children before and after pyeloplasty. The pyeloplasty was considered successful in 30 and unsuccessful in 5. Both anatomic and functional criteria were used. The anatomic parameters included the degree of hydronephrosis, the appearance of the renal parenchyma, the quality of the nephrogram and the presence of crossing vessels. The functional criteria included the renal transit time, the calyceal transit time, the volumetric differential function, the Patlak differential function, the difference between the volumetric and Patlak differential function and the Patlak number per milliliter of renal tissue. No single parameter was sufficient to fully characterize UPJ obstruction, but by synthesizing all the information we were able to subdivide UPJ obstruction into compensated, decompensated and uropathic kidneys. Decompensated systems had the most significant improvement following successful pyeloplasty. Compensated systems showed little improvement in renal function, and uropathic kidneys were associated with a poor prognosis. It is clear that not all UPJ obstructions are the same, and it seems logical that treatment should be individually tailored rather than using a standard approach for all cases. Because MR urography can identify pathophysiological differences in children with UPJ obstruction that are occult to renal scintigraphy, it has an important potential role in identifying those who will benefit most from pyeloplasty and those who are probably best observed.
本文基于本次研讨会的上一篇文章展开，展示了磁共振尿路造影如何有助于对肾盂输尿管连接部梗阻患儿进行术后评估。通过分析术后结果，我们对术前评估有了新的认识。利用磁共振尿路造影，我们将生理和解剖评估同时进行，这使我们能够识别与引流受损和梗阻相关的肾脏病理生理学变化。我们研究了35例肾盂成形术前后的患儿。30例肾盂成形术被认为成功，5例失败。同时使用了解剖和功能标准。解剖参数包括肾积水程度、肾实质外观、肾图质量和交叉血管的存在。功能标准包括肾脏转运时间、肾盏转运时间、容积微分功能、Patlak微分功能、容积和Patlak微分功能之间的差异以及每毫升肾组织的Patlak数。没有单一参数足以完全表征肾盂输尿管连接部梗阻，但通过综合所有信息，我们能够将肾盂输尿管连接部梗阻细分为代偿性、失代偿性和肾病变肾脏。成功的肾盂成形术后，失代偿系统改善最为显著。代偿系统的肾功能改善甚微，而肾病变肾脏预后较差。显然，并非所有肾盂输尿管连接部梗阻都是相同的，治疗应个体化定制而非采用统一的标准方法似乎是合理的。因为磁共振尿路造影能够识别肾盂输尿管连接部梗阻患儿中肾脏闪烁显像难以发现的病理生理差异，所以它在确定哪些患儿将从肾盂成形术中获益最大以及哪些患儿可能最好进行观察方面具有重要的潜在作用。
